用格子Boltzmann方法模拟液滴撞击固壁动力学行为

A simulation of impact of droplets on solid surfaces by using the Lattice Boltzmann method

首次用格子Boltzmann方法中的伪势模型对液滴撞击固壁的动力学行为进行了数值模拟。详细研究了液滴在壁面上的流动状态以及各种因素对撞击过程的影响。通过数值模拟得到:壁面的可润湿性越小,液滴越容易发生反弹,液滴的回缩速度越快;液滴的撞击速度越大,所得到的相对直径越大,回缩速度越快;液滴的粘性越小,所得到的相对直径越大;液滴的表面张力越大,液滴越容易发生反弹现象。另外,液滴的最大相对直径与We数满足一定的线性关系,这些结果与前人的理论预测和实验结果完全吻合。

The lattice Boltzmann potential model was firstly used to simulate the droplets impacting on solid surfaces. The flow state of droplets on solid surfaces and the effects of the impact parameters on the droplet impingement have been studied. It has been observed that surface wettability has a significant influence on the droplets impacting dynamics, the less of surface wettability, the easier to rebound and the faster of the recoiling speed. The higher of the impact speed and the smaller of the liquid viscosity, the bigger of the relative diameter is. In addition, the maximal relative diameter has linearity relation with the Weber number. Simulation results are consistent with the previous theory prediction and experimental results.